This invention relates to an electrical plug with molded on prongs, specifically the electrical wires are mounted on the prongs by detachable wire loops without using screws.
At present, electrical wires are normally mounted onto contact prongs of an electrical plug by using screws, but when a wire is connected to a contact prong by the use of a screw, the bare end of the wire is first wrapped around the screw and then the screw is tightened, if the wire wrapped around the screw is too short, it may become loose; but if too much wire is used in wrapping, it can lead to difficulty in closing the cover because of limited space in the connecting chamber. The wire may also become loose, if its bare end is wrapped around the screw in the direction opposite to the tightening direction of the screw.
Although the use of screws for wire and prong connection in some plugs have been eliminated, and replaced by wrapping a wire on a prong, hooking a wire on a prong, or clamping a wire with the cover, they all pose possible hazards of allowing the wire to slip out easily from the prong if the wire were pulled, or creating electrical sparks between the wire and the prong due to lack of tight contact.
In addition, some plugs also require the use of screws to attach the contact prongs onto the body, some clamp the prongs onto the body but require a screw to join the body into one piece, and some use an insert to separate and stabilize the contact prongs through a hole at the bottom. Generally, completing the mounting process is costly and time-consuming. Since contact prongs are subject to a rocking motion during each plugging or unplugging operation, if the contact prongs are assembled onto the body, the stability of the installation would be subject to question and would depend on the individuals involved. Hence, they should not be compared to this invention.
In a more recent invention called extention cord, the prongs and the wires are all molded together in the plug. Although this provides a very secure hold on the prongs, wires cannot be mounted or remounted at will, so it also should not be compared to this invention.